Despite a decline in violence in Iraq, Northern Iraq has become more violent than other regions as al-Qaida and other militants move there to avoid coalition operations elsewhere, the region's top US commander said Monday. Army Maj. Gen. Mark P. Hertling said al-Qaida cells still operate in all the key cities in the north. "What you're seeing is the enemy shifting," he told Pentagon reporters in a video conference from outside Tikrit in northern Iraq. Hertling said militants have been pushed east to his area from Anbar by the so-called Awakening movement, in which local tribes have allied with the coalition against al-Qaida. Others have been pushed north to his area from the Baghdad region, where this year's US troop escalation has made more operations possible.